Edible fat-containing product and process for preparing same

ABSTRACT

The present invention pertains to edible fat-containing products, in particular spreads, comprising at least 5% of hardstock indigestible polyol fatty acid polyesters, the fat-phase being characterized by an, at least, two-peaked DSC-curve. The invention further pertains to a process for the preparation of such products.

This is a continuation, application of Ser. No. 07/231,118, filed Aug.11, 1988 now abandoned.

BACKGROUND OF THE INVENTION

The invention relates to edible fat-containing products comprisingindigestible polyol fatty acid polyesters. In particular, although notexclusively, the invention relates to such products of the emulsiontype, such as margarines and low-fat spreads. The invention furtherrelates to processes for the preparation of such products.

Polyol fatty acid polyesters, and in particular, the sugar fatty acidpolyesters, such as e.g. the sucrose fatty acid polyesters, are known assuitable low-calorie fat-replacers in edible products. Substantiallyindigestible for human beings they have physical and organolepticproperties very similar to triglyceride oils and fats conventionallyused in edible products. Polyol fatty acid polyesters are also reportedto have use as pharmaceutical agents e.g. in view of their ability totake up fat-soluble substances, such as in particular cholesterol, inthe gastro-intestinal tract, and subsequently remove those substancesfrom the human body. Accordingly, it is attractive to replace at leastpart of the fat in edible fat-containing products by polyol fatty acidpolyesters.

It is further reported that in food products the use of polyol fattyacid polyesters which are liquid at body temperature, may give rise tothe so-called problem of anal leakage. Accordingly, it is particularlyattractive to replace the more solid part (hardstock) of the fat bycounter-part polyol fatty acid polyesters.

Edible fat-containing products comprising indigestible polyol fatty acidpolyesters are known in the art, and described in eg U.S. Pat. Nos.3,600,186, 4,005,195, 4,005,196, 4,034,083 and EP Pat. Publ. Nos. 0 233856, 0 236 288, and 0 235 836.

In this specification, unless otherwise indicated, the term 'fat' refersto edible fatty substances in a general sense, including natural orsynthesized fats and oils consisting essentially of triglycerides suchas, for example, soybean oil, sunflower oil, palm oil, coconut oil, fishoil, lard and tallow, which may have been partially or completelyhydrogenated or modified otherwise, as well as non-toxic fatty materialshaving properties similar to triglycerides, which materials may beindigestible, such as for example waxes, e.g. jojoba oil andhydrogenated jojoba oil, and polyol fatty acid polyesters referred tohereinafter in more detail. The terms fat and oil are usedinterchangeably.

In this specification the term 'polyol' is intended to refer to anyaliphatic or aromatic compound which comprises at least four freehydroxyl groups. Such polyols in particular include the group of sugarpolyols, which comprises the sugars, i.e. the mono-, di-andpolysaccharides, the corresponding sugar alcohols and the derivativesthereof having at least four free hydroxyl groups. Examples of sugarpolyols include glucose, mannose, galactose, xylose, fructose, sorbose,tagatose, ribulose, xylulose, maltose, lactose, cellobiose, raffinose,sucrose, erythritol, mannitol, lactitol, sorbitol, xylitol andalpha-methylglucoside. A generally used sugar polyol is sucrose.

In this specification the term 'polyol fatty acid polyester' is intendedto refer to any such polyesters or mixtures thereof of which, on anaverage, more than 70 % of the polyol hydroxyl groups have beenesterified with fatty acids.

In this specification by 'indigestible' is meant that at least about 70% by weight of the material concerned is not digested by the human body.

In this specification by 'hardstock' is meant that part of the fatcomposition characterized by a slip melting point of above 36° C. 'Slipmelting point' is defined as the temperature at which the amount ofsolid phase in the melting fat has become so low that an air bubble isforced upwards in an open capillary filled with the fat.

Fat-containing products and in particular, emulsion-type products suchas margarines and low-fat spreads, have to comply with requirements suchas oral response, thermal stability, cycle stability, spreadability,melting behaviour and the like. Often they have to comply with suchrequirements simultaneously.

In particular, for margarines and low-fat spreads which containrelatively large amounts of polyunsaturated components, or requireincreased softness at lower (refrigerator) temperatures, it can bedifficult to simultaneously comply with the requirements for cyclestability, thermal stability and acceptable taste properties.

Stability against temperature changes (cycle stability) is important inview of temperature changes during transport and storage as well astemperature changes which may frequently occur during household use.Improved storage temperature cycle stability is therefore advantageous,if not essential.

Heat stability, i.e. stability in terms of the absence of phaseseparation and of oil exudation, determines the ambient temperatures atwhich the product can be used. It will be clear that heat stabilityrequirements are dependent of the climatic zone involved.

In general the heat stability is governed by the amount of hardstock,i.e. the amount of higher melting fats. A better heat stability,however, in general will result in a deterioration of the oral response,especially after temperature cycling. This is because the oral responselargely depends on the melting behaviour of the fat phase.

Although not wishing to be bound by theory, it is believed that thedifficult compatibility of heat stability, good oral response andcycling stability stems from the fact that good heat stability (e.g.heat stability at 30° C. for 24 hours) generally requires fat blendcompositions containing relatively high amounts of higher melting fatfractions such as in particular fat fractions having melting pointsabove mouth temperature. These higher melting fat fractions are believedto be responsible for the adverse effects on oral response and cyclingstability.

Generally, in conventional fat-containing products the higher meltingfat fractions crystallize in mixed crystals of non-equilibriumcomposition, which incorporate considerable amounts of the lower-meltingfat fractions. In a well formulated blend the melting point of the mixedcrystals is just below mouth temperature. Accordingly, in the mouth suchblends will melt entirely, not giving rise to waxiness and, in the caseof emulsions, fully releasing the salt and flavour compounds present inthe water phase.

However, when conventional fat-containing products are subjected totemperature cycling, the mixed crystals demix, and a separate, purerfraction of the higher melting fats crystallizes. In this process anetwork of crystals is formed, which, if a dispersed water-phase ispresent, surrounds and stabilizes the dispersed water droplets in theform of shells. In the mouth the non- or only partially melting networkof crystals introduces a waxy taste, and prevents release of salt orflavour compounds from the dispersed water droplets which remainstabilized.

Conventional products displaying good heat stability often combine thisproperty with a rather bad cycling stability and oral response. Viceversa, conventional products having improved cycle stability, due to thepresence of a relatively small amount of high melting fats often sufferfrom a poor heat stability.

SUMMARY OF THE INVENTION

It is now an object of the present invention to provide ediblefat-containing products comprising indigestible polyol fatty acidpolyesters as hardstock which products are characterised by an improvedcombination of properties, in particular with regard to thermalstability, oral response and storage temperature cycle stability.

It has been found that, if at least a significant part of the hardstockpolyol fatty acid polyesters are processed such that crystallizationtakes place before full mixing with the remaining fat fraction,fat-containing products can be obtained meeting the above object. Theseproducts are characterised by multi-peaked differential scanningcalorimetry (DSC) curves showing separate fat peaks at both sides of 36°C.

Accordingly, in a first aspect of the present invention there areprovided fat-containing products comprising at least 5 %, calculated byweight of the total amount of fat, of hardstock indigestible polyolfatty acid polyesters, the product having a differential scanningcalorimetry curve showing at least one fat peak above 36° C., and atleast one fat peak below 36° C.

In a further aspect of the invention there is provided a process for thepreparation of fat-containing products comprising at least 5%,calculated by weight of the total amount of fat, of hardstockindigestible polyol fatty acid polyesters, the process comprising thestep of initially processing the product in two or more separatefat-containing fraction under such conditions that the fat in at leastone of the fractions has partly or fully crystallized before the two ormore fractions have been fully mixed.

DETAILED DESCRIPTION OF THE INVENTION

It has been found, that the fat-containing products, in particular thewater-in-oil, oil-in-water and oil-in-water-in-oil emulsion types,prepared or preparable by the separate processing of fat fractions inaccordance with the present invention, have greatly improvedcharacteristics in terms of oral response, thermal stability and cyclestability.

It has further been found that the products in accordance with theinvention can be formulated to have a reduced hardness at 5° C. and anequal or higher hardness at 20° C. compared to conventionalfat-containing products based on the same components. This 'flatter'hardness-versus-temperature line is especially important for householdspreads, where the cold spread, straight from the refrigerator, has tobe spreadable, but on the other hand should not be too soft at roomtemperature.

An essential ingredient in the products according to the presentinvention are hardstock indigestible polyol fatty acid polyesters. Thehardstock polyol fatty acid polyesters may be the only such polyesterspresent but they may also be part of a mixture of polyol fatty acidpolyesters or a polyester blend, provided the overall polyol fatty acidpolyester composition comprises a sufficient amount of hardstock polyolfatty acid polyesters.

In addition to the hardstock polyol fatty acid polyesters it is possibleto further include conventional hardstocks triglyceride fats. However,it is preferred that the hardstock used in the products of the inventionconsists of over 50%, preferably of over 80% or even 90% by weight ofpolyol fatty acid polyesters. Most preferably the hardstocksubstantially completely consists of polyol fatty acid polyesters.

The total amount of hardstock in the products of the invention is atleast 5% calculated by weight of the total amount of fat. Preferably theamount of hardstock lies in the range of 20 to 70%, the range of 30 to50% being preferred most.

By variation of the particular blend of fatty acid residues used in thesynthesis the melting point of the polyol fatty acid polyesters can beinfluenced. More saturated and/or long-chain fatty acid residues resultin a higher melting point than unsaturated and/or short-chain fatty acidresidues. The slip melting point of the hardstock polyol fatty acidpolyesters preferably lies within the range of from 37° to 55° C., inparticular of from 40° to 50° C.

Suitable polyol fatty acid polyesters have been defined in chemicalterms hereinbefore. Preferably, polyol fatty acid polyesters derivedfrom sugars or sugar alcohols are applied, and in particular, sugarfatty acid polyesters derived from disaccharides, such as sucrose. Verysuitable have been found sugar fatty acid polyesters of which at least50% of the fatty acid residues are derived from saturated fatty acids,in particular saturated C₈ -C₂₂ fatty acid. Sucrose polyesters of whichat least 70% of the fatty acid residues are derived from C₁₂ -C₁₈ fattyacids, are preferred.

In general fatty acids per se or naturally occurring fats and oils maybe used as source for the fatty acid residues in the polyol fatty acidpolyesters. Conventional techniques may be used to introduce, ifnecessary, the required degree of saturation. Suitable such techniquesinclude full or partial hydrogenation, interesterification,transesterification and fractionation, and may be used before or afterconversion of the polyols to polyol fatty acid polyesters.

Suitably polyol fatty acid polyesters are used which are completely orpartly derived from trans-hydrogenated triglycerides or thecorresponding lower alkylesters thereof, as described in EP 0 235 836.Alternatively, the desired level of trans fatty acid residues may alsobe introduced by first converting to the polyol fatty acid polyester andsubsequent trans-hydrogenation.

As defined hereinbefore polyol fatty acid polyesters may be applied ofwhich, on an average, more than 70 % of the polyol hydroxyl groups havebeen esterified with fatty acids. Preferably polyol fatty acidpolyesters are used with higher degrees of conversion, in particularpolyol fatty acid polyesters of which, on an average, more than 85 % oreven over 95 % of the polyol hydroxyl groups have been esterified withfatty acids.

The products in accordance with the invention in general have an overallfat content between 35 and 100 % by weight. In a preferred aspect of theinvention such products are water-in-oil or oil-in-water-in-oilemulsions containing 35-90 % by weight of fat, margarine-type spreadshaving a fat content of 65-90 % by weight being preferred most. In analternative aspect of the invention such products are margarine-likeproducts containing over 95 %, in particular, about 98 % of fat, such asare used for baking purposes.

In addition to the hardstock fat the products of the invention generallycomprise conventional oils and fats which may be of both animal andvegetable origin. Suitable conventional triglyceride fats and oilsinclude, optionally partially hydrogenated, coconut oil, palmkernel oil,palm oil, marine oils, lard, tallow fat, butter fat, soybean oil,safflower oil, cotton seed oil, rapeseed oil, poppy seed oil, corn oilsunflower oil and mixtures thereof. Of these oils sunflower oil ispreferred.

The non-hardstock part of the overall fat composition may also compriseindigestible oils, such as liquid polyol fatty acid polyesters. Suitablyliquid polyol fatty acid polyesters, i.e. having slip melting pointsbelow 36° C., can be used to replace fully or partially thenon-hardstock part of the fat composition. Also, instead of separatehardstock and non-hardstock polyol fatty acid polyester fractions,polyol fatty acid polyesters which comprise both hardstock andnon-hardstock fractions may be advantageously used.

It may also be of advantage to obtain high-melting and low-melting fatfractions by fractionating a single fat blend, such as partiallyhardened soybean oil or a sugar polyester blend comprising both solidand liquid fractions, and use the high-melting and low-melting fractionsseparately.

It has been well recognised that fat-containing products containingrelatively large amounts of digestible polyunsaturated fatty acidresidues are attractive for their cholesterol-lowering effect. Suchproducts are in particular those in which the fatty acid residues in thedigestible part of the fat composition comprise a maximum of 35 % ofsaturated fatty acid residues. A useful characteristic to scalefat-containing products for their cholesterol-lowering effect is theratio of polyunsaturated to saturated fatty acid residues (in thiscontext only fatty acid residues in digestible fats are considered). Thehigher this ratio, the stronger the cholesterol-lowering effect. Sincelinoleic acid is the most important polyunsaturated fatty acid, insteadof the above ratio in practice the ratio of linoleic acid to saturatedfatty acid residues (LA/SFA ratio) can be used.

Products in which in particular the conventional saturated fat fraction(i.e. the conventional hardstock) is fully or partially replaced byindigestible polyol fatty acid polyesters having characteristics similarto the conventional hardstock fat fraction, allow an appreciable anddesirable increment in the LA/SFA ratio. In the products according tothe invention LA/SFA ratios are achieved of over 5, such as 6 to 8. Ifso desired, LA/SFA ratios can be achieved of over 10.

Fat-containing products, such as margarines, having a high amount ofunsaturated components are of course characterized by the presence oflarge amounts of liquid oil, which leads to the problem that it isdifficult to have sufficient thermal stability and hardness. The presentinvention allows products displaying an improvement in the hardness,without the necessity of a decrease in the amount of unsaturatedcomponents, and without a deterioration of the oral response. The amountof polyunsaturated fatty acid residues, such as in particular linoleicfatty acid residues, in the present fat product is preferably between 30and 80 %, in particular at least 40 %, or even 50 or 60 % by weight ofthe total amount of digestible fatty acid residues present in the fatphase.

Since the considerations given hereinabove also apply for fat-containingproducts having lower fat contents, such as low-fat spreads with fatcontents of between 35 and 65 % by weight the invention is equallydirected to those.

Although the invention is especially directed to products of thewater-in-oil and oil-water-in-oil emulsion type, such as margarines andspreads, the advantages are equally achieved in products of theoil-in-water emulsion type, such as mayonnaise, or non-emulsion type,such as shortenings, which incorporate significant amounts of hardstock.

In the products according to the invention conventionally used fat- andwater-soluble additives, such as emulsifiers, milk, proteins,preservatives, vitamins, in particular, vitamins A, D and E, salt andflavour compounds, may be incorporated.

One of the aspects of the products according to the present invention isthe presence of a fat peak in the DSC-curve above 36° C., i.e. a peak ofwhich the top is located above 36° C. Preferably at least 80% of thesurface area of the peak, i.e. the surface area between the base lineand the line generated by the differential scanning calorimeter, isabove 36° C. It is thus possible that part of the lower temperature tailof the peak is located below 36° C. When determining the surface area ofindividual peaks, in case peaks overlap, it is assumed that the peaksare symmetrical.

In this specification by 'peak in the DSC-curve' is meant an absolute orrelative maximum in the DSC-curve. The term 'fat peak' is intended toexclude those peaks or parts of peaks which are not attributable to thefat part of the product.

At least one further fat peak should be present below 36° C. This may bea peak in the temperature range of 20° and 35° C., but also fat peaks attemperatures below this range correspond to DSC-curves in accordancewith the present invention. Such fat peaks then correspond to lowercrystallizing fat fractions. In the products according to the inventionat least two separately melting fat fractions are present.

It is preferred that the DSC-curve surface area (as definedhereinbefore) below 36° C. is at least equal to the surface area above36° C.

The DSC-temperature peaks of fat-containing products can be determinedin the conventional way using a differential scanning calorimeter. Ashort survey of this method with some literature references is given inthe Ullmanns Encyklopadie der technischen Chemie, 4. Auflage, Band 5,pages 793-795. In this application all DSC-curves areDSC-melting-curves.

The fat-containing products in accordance with the invention arecharacterised by at least 20 % by weight of the crystallized fat beingpresent in the form of fat particles having sizes between 1 and 20micrometres. Preferably at least 50 % by weight of the crystallized fatis present in the form of fat particles having sizes of more than 1micrometre.

Most preferred are products wherein at least 40 % by weight of thecrystallized fat is present in the form of fat particles having sizesranging from 1-12 micrometres. In this context the term 'size' isintended to refer to the maximum diameter of the crystallized fatparticles.

In general the fat product of the invention has an overall N₄₀ below 10,more preferably it has an N₃₅ below 10 and an N₂₀ below 30, preferablybetween 8 and 25. The N-values are measured by using the NMR method asdescribed in Journal of American Oil Chemists' Society, 51 (1974), 316by Van Putte et al.

The process for the preparation of the fat-containing products accordingto the present invention comprises as an essential step the initialsplit processing of the overall product in at least and preferably twoseparate fat-containing fractions which differ in the slip melting pointof their fat fractions, such that at least partial crystallization takesplace in, particularly, the fat fraction having the higher slip meltingpoint before full mixing with the further fat-containing fractions hasbeen effected.

In general a first separately processed fat-containing fraction ischaracterized by a fat phase having a slip melting point below 36° C.,preferably below 35° C., or even 30° C. This fat phase may besubstantially liquid before full mixing with the further fat-containingfractions, but it has been found of advantage when the fat in the firstfraction contains some crystallized fat at the point of mixing, such asat least 1 % by weight, preferably between 2 and 20 % by weight of thefraction.

The fat phase in the second separately processed fat-containing fractionin general has a slip melting point above 36° C., preferably between 37°and 55°, and most preferably between 40° and 50° C. The fat phase inthis fraction, which comprises the hardstock fats or at least asignificant part thereof, such as at least 60 %, and preferably at least80 % by weight, in general will contain crystallized fat at the point ofmixing, although also crystal formation may take place during the mixingwith further fat-containing fractions provided mixing conditions aresuch that partial crystallization has taken place before full mixing.Typical amounts of crystallized fat in this second fat-containingfraction before full mixing are between 2 and 30 % by weight, butpreferably not more than 15 % by weight of the fraction.

It is preferred that the slip melting points of the fats in twoseparately processed fat-containing fractions differ by at least 5° C.,more in particular 10° C. The magnitude of this difference influencesthe beneficial effects that may be derived from the process according tothe present invention; the beneficial effect being more pronounced whenthe difference is larger.

The separately processed fat-containing fractions may comprise only fatcomponents, but they may also be in the form of water-in-oil oroil-in-water emulsions, such as creams.

In a preferred aspect of the process of the invention, which isparticularly directed to the preparation of spreads, a first fat or fatblend is emulsified with an aqueous phase. The temperature of thewater-in-oil emulsion so obtained, if necessary, is adjusted to a valuebelow 15° C., more in particular to below 10° C. More preferably, thetemperature is adjusted to a value between 5° and 10° C. It is importantto apply the correct temperature, as the second fat-containing fraction(discussed hereunder) has to crystallize due to the 'cold-content' ofthe emulsion, as preferably no further cooling steps are provided for.It is also important that the cold emulsion already has its finalcharacter, i.e. phase-inversion should have taken place already, andalso the water droplet distribution should be near to its final status.The emulsion is preferably prepared by treatment in two A-units(scraped-surface heat exchangers) followed by a C-unit (pen stirrer),although it is possible to use other systems as well. The 'cold'water-in-oil emulsion, preferably containing at least 1 % by weight ofcrystallized fat, is thereafter mixed with a second fraction essentiallyconsisting of a second fat or fat blend having a slip melting pointabove that of the first fat or fat blend which second fat or fat blendis at such a temperature that the solids content thereof is between 2and 30 % by weight.

More preferably the emulsion of the first fat-containing fractioncomprises from 2 to 20 % by weight of crystallized fat before mixing.The slip melting point of the first fat or fat blend is preferably below35° C. More preferably, the slip melting point of the fat in the firstfraction is below 30° C. and the slip melting point of the fat in thesecond fraction is above 40° C. In this case a very pronounced effect isnoted, namely that a product is obtained combining a high thermalstability and with a very good stability against temperature cycling,presumably due to the presence of some kind of network of the second fator fat blend. The presence of such a network, however, does notinfluence the taste of the fat spread negatively.

The emulsion of the first fat-containing fraction usually contains oneor more emulsifiers that favour water-in-oil-emulsion, whereas also thefat- and water-soluble additives required for the final product areincorporated therein.

The second fat or fat blend comprises a partially molten fat, or a fatcontaining up to 30, preferably up to 25 % by weight of solids, morepreferably not more than 10 % by weight solids (crystallized fat) at thetemperature at which it is fed to the mixing unit for mixing with thecold emulsion, which temperature preferably is above 20.C. At the momentof mixing the second fat or fat blend with the water-in-oil emulsion,the second fat or fat blend may be in an supercooled state, as aconsequence of which retarded crystallization may occur.

In the above preferred aspect of the process of the invention thehardstock polyol fatty acid polyesters and, optionally, the high meltingtriglycerides present in the second fat fraction, are mixed with thecold water-in-oil emulsion, comprising crystallized low meltingtriglycerides, as a result of which separately crystallized fat crystalswill be present in the final product. Although we do not wish to bebound by theory, it is believed that this separate crystallization isresponsible for the beneficial effects obtained by the present process.

By separately preparing the cold water-in-oil emulsion, an emulsion isobtained, wherein the surface of the water droplets is almost completelyoccupied with crystals of the low-melting fat fraction. On mixing thisemulsion with the second fat fraction a final product is obtained inwhich the surface of the water droplets is still occupied with the lowmelting fat fraction. These products have a supreme oral responsebecause the flavour release of the water droplets is not hindered by thepresence of a shell of high melting fat crystals surrounding the waterdroplets. The separately crystallized high melting fat fraction,however, are present in the form a network, stabilizing the product, andpreventing oil exudation at temperatures as high as 30° C.

The relative amounts of the two separate process streams can varywidely, depending on the type of fats and the amount of water present. Alower limit for the amount of water-in-oil-emulsion is 17.5 % by weight,corresponding to 82.5 % by weight of second fat fraction. The upperlimit for the water-in-oil-emulsion is 97 % by weight, corresponding to3 % by weight of second fat fraction. In general the contribution of thewater-in-oil-emulsion will not exceed 90 % by weight.

In a further aspect of the invention an alternative preferred processcomprises the step of preparing a first fraction essentially consistingof a fat or fat blend which includes part of the hardstock fats. Thisfirst fat or fat blend is thereafter mixed with a oil-in-water emulsion,such as in particular a cream, comprising the major part of thehardstock fats, preferably more than 60 % of the hardstock fats. Thetemperature and mixing profile may be essentially similar to the onedescribed hereinbefore.

The conditions during the mixing of the two fractions of the spread caninfluence the product properties to a large degree. Short residencetimes and/or low shear favour the formation of a separate high meltingcrystal network. The shear rate should be low in order to prevent thesubstitution of low melting fat on the water droplet surface by highmelting fat crystals, and also to avoid the breaking-up of the networkof high melting fat crystals, which stabilizes the product.

Suitable mixers for this purpose are well-known. Examples thereof arestatic mixers and jet mixers. It is also possible to use a cavitytransfer mixer, as described in WO-A 8 303 222.

After the mixing step, the product is fed to a packing line, withoutfurther working or cooling, and the spread is packed. The packed spreadis then stored during which storage the final properties are obtained.

In the art it is reported that upon consumption of the fat-containingproduct the presence of polyol fatty acid polyesters may have adepletory effect on fat-soluble components, such as in particular, thefat-soluble vitamins A, D and E. The process in accordance with theinvention allows a reduction of any such risk. In a preferred aspect ofthe invention any vitamins to be added are incorporated into a firstseparately processed fat-containing fraction which is substantially freefrom any indigestible polyol fatty acid polyesters. Accordingly, thehardstock polyol fatty acid polyesters are incorporated into the one ormore further separately processed fractions, and at least partialcrystallisation of the hardstock polyesters takes place before thevitamin-containing and polyester-containing fractions are mixed.

By application of the process of the present invention using saidvitamin-containing and said hard-stock polyester-containing fractionsany depletory effect on said vitamins has been reduced.

The invention is now further illustrated with reference to the followingexamples.

Example 1

A spread was prepared using a first and a second fraction having thefollowing compositions (percentages being by weight of the finalcomposition):

    ______________________________________                                        first fraction (water-in oil emulsion)                                        sunflower oil         21.0%                                                   sucrose fatty acid polyester (*)                                                                    7.0%                                                    NaCl                  0.2%                                                    gelatin               1.4%                                                    sodium caseinate      2.1%                                                    emulsifiers           0.3%                                                    minors                0.2%                                                    water                 37.8%                                                   (pH 5.1)                                                                      second fraction (cream)                                                       sucrose fatty acid polyester (*)                                                                    12.0%                                                   NaCl                  0.1%                                                    gelatin               0.6%                                                    sodium caseinate      0.9%                                                    emulsifiers           0.1%                                                    minors                0.1%                                                    water                 16.2%                                                   (pH 5.1)                                                                      ______________________________________                                         (*) polyester fatty acid residues derived from 55% of fully hardened          soybean oil and 45% of touchhardened soybean oil; OHnumber 10.2               corresponding to a degree of conversion of about 95%; slip melting point      about 42° C.                                                      

The first fraction was initially prepared as a water-continuous premixwhich was processed using an A-unit (shaft speed 200 rpm; exittemperature 11.3° C.) and a subsequent C-unit (shaft speed 1460 rpm;exit temperature 26° C.) yielding a water-in-oil emulsion comprisingabout 4.5% of solids. Parallel thereto the second fraction was processedusing a single A-unit (shaft speed 1000 rpm; exit temperature 39° C.)and subsequently injected into the stream of said first fractionimmediately after the C-unit. The combined fractions were then furtherprocessed using an A-unit (shaft speed 500 rpm; exit temperature 13.3°C.) and a C-unit (shaft speed 1500 rpm; exit temperature 15° C.). Afterthe C-unit the final product had a solids level of 13.4%.

For reasons of comparison a premix of the same overall productcomposition was also processed using the following sequence:

    ______________________________________                                        unit type                                                                            shaft speed                                                                              exit temperature                                                                           % of solids at exit                            ______________________________________                                        A      500 rpm    37.8° C.                                                                            0.0                                            C      1500 rpm   31.0° C.                                                                            2.6                                            A      500 rpm    26.8° C.                                                                            3.4                                            C      150 rpm    28.0° C.                                                                            6.2                                            ______________________________________                                    

From the hardness (1) and salt-release characteristics shown in Table 1it is clear that the product processed in accordance with the presentinvention, although similar to the conventionally processed product(reference) in terms of salt release, is significantly softer at allevaluation temperatures.

(1) Hardness C-values and the measurement thereof are described in theJournal of American Oil Chemists' Society 36 (1959), 345.

                  TABLE 1                                                         ______________________________________                                                   product processed                                                                          reference                                                        according to invention                                                                     product                                               ______________________________________                                        hardness                                                                      C.sub.5      310            1200                                              C.sub.10     230            1070                                              C.sub.15     180             720                                              C.sub.20     145             435                                              salt release                                                                  at 37° C.                                                                             18.6            20.0                                           100% (°C.)                                                                            40.1            41.4                                           ______________________________________                                    

Example 2

A spread was prepared using a first and a second fraction having thefollowing compositions (percentages being by weight of the finalcomposition):

    ______________________________________                                        first fraction (water-in-oil emulsion)                                        sunflower oil           16.5%                                                 partially hardened soybean oil                                                                        44.0%                                                 skim milk powder        1.0%                                                  NaCl                    1.7%                                                  minors                  0.5%                                                  water                   15.6%                                                 second fraction (essentially hardstock fat)                                   sucrose fatty acid polyester                                                                          18.6%                                                 (similar to example 1)                                                        sunflower oil           2.1%                                                  ______________________________________                                    

The first fraction (slip melting point of fat phase 28° C.) wasprocessed in a two subsequent A-units (scraped surface heat exchanger)and one C-unit (pen stirrer) yielding an emulsion at 8° C. comprisingabout 4% of solids. Parallel thereto the second fraction (slip meltingpoint 45° C.) was processed in an A-unit followed by a C-unit yielding afat phase at 42° C. comprising about 13$ of solids. Both fraction werefed to a cavity transfer mixer and filled into tubs to yield a productof about 9% of solids overall at 18° C.

The hardness characteristics of the product were as follows:

    ______________________________________                                                C.sub.5                                                                            400                                                                      C.sub.20                                                                           100                                                                      C.sub.25                                                                           <100                                                             ______________________________________                                    

Example 3

A spread was prepared using a first and a second fraction having thefollowing compositions:

    ______________________________________                                        first fraction (water-in-oil emulsion)                                        sunflower oil           48.5%                                                 sucrose fatty acid polyester                                                                          12.0%                                                 (similar to example 1)                                                        skim milk powder        1.0%                                                  NaCl                    1.7%                                                  minors                  0.5%                                                  water                   15.6%                                                 (slip melting point of fat phase 32° C.)                               second fraction (essentially hardstock fat)                                   sucrose fatty acid polyester                                                                          18.6%                                                 sunflower oil           2.1%                                                  (slip melting point 45° C.)                                            ______________________________________                                    

The first fraction was processed in a two subsequent A-units and oneC-unit yielding an emulsion of 8° C. comprising 9.5% of solids. Parallelthereto the second fraction was processed in an A-unit followed by aC-unit yielding a fat phase of 42° C. comprising about 11% of solids.Both fraction were fed to a cavity transfer mixer and filled into tubsto yield a product of about 15% of solids overall at 18° C.

The hardness characteristics of the product were as follows:

    ______________________________________                                                C.sub.5                                                                            800                                                                      C.sub.20                                                                           450                                                                      C.sub.25                                                                           300                                                              ______________________________________                                    

Example 4

A spread was prepared using a first and a second fraction having thefollowing compositions:

    ______________________________________                                        first fraction (water-in-oil emulsion)                                        sunflower oil           42.2%                                                 sucrose fatty acid polyester                                                                          10.6%                                                 (similar to example 1)                                                        skim milk powder        1.0%                                                  NaCl                    1.7%                                                  minors                  0.5%                                                  water                   15.6%                                                 (slip melting point of fat phase 32° C.)                               second fraction (essentially hardstock fat)                                   sucrose fatty acid polyester                                                                          25.6%                                                 sunflower oil           2.8%                                                  (slip melting point 45° C.)                                            ______________________________________                                    

The first fraction was processed in a two subsequent A-units and oneC-unit yielding an emulsion of 8° C. comprising 9.4% of solids. Parallelthereto the second fraction was processed in an A-unit followed by aC-unit yielding a fat phase of 43° C. comprising about 6% of solids.Both fraction were fed to a cavity transfer mixer and filled into tubsto yield a product of about 15% of solids overall at 18° C.

The hardness characteristics of the product were as follows:

    ______________________________________                                                C.sub.5                                                                            700                                                                      C.sub.20                                                                           400                                                                      C.sub.25                                                                           200                                                              ______________________________________                                    

Example 5

A spread was prepared using a first and a second fraction having thefollowing compositions:

    ______________________________________                                        first fraction (essentially fat)                                              hardstock sucrose fatty acid polyester (*)                                                              11.2%                                               sunflower oil             33.6%                                               minor ingredients         0.2%                                                second fraction (cream plus added hardstock fats)                             hardstock sucrose fatty acid polyester                                                                  22.0%                                               sodium caseinate          3.0%                                                gelatine                  2.0%                                                salt                      1.8%                                                minor ingredients         0.2%                                                water                     26.0%                                               ______________________________________                                         (*) polyester fatty acid residues derived from 57% of fully hardened palm     kernel oil and 43% of fully hardened palm oil; OHnumber 5.7 corresponding     to a degree of conversion of about 97%; slip melting point about              40° C.                                                            

The first fraction was processed in an A-unit (500 rpm) yielding a fatphase of 10° C. comprising about 16% of solids. The second fraction wasprocessed in an A-unit (1000 rpm) yielding a cream of 50° C. comprisingonly 2% of solids. Both fraction were fed to the same C-unit and mixedat 2500 rpm to give about 3% of solids overall at 35° C. Subsequently,the mixture was worked in an A-unit (1500 rpm) yielding the tub-fillablespread product of 17° C.

The hardness and salt release characteristics of the product were asfollows:

    ______________________________________                                        hardness        C.sub.5      650                                                              C.sub.10     575                                                              C.sub.15     250                                                              C.sub.20     180                                              salt release    at 33° C.                                                                            16.3%                                                           at 37° C.                                                                            99.7%                                                           at 37.3° C.                                                                         100.0%                                           ______________________________________                                    

What is claimed is:
 1. Edible fat-containing product comprising at least5 %, calculated by weight of the total amount of fat, of hardstockindigestible polyol fatty-acid polyesters, the product having adifferential scanning calorimetry curve showing at least one fat peakabove 36° C., and at least one fat peak below 36° C.
 2. Productaccording to claim 1 which comprises 20 to 70 %, calculated by weight ofthe total amount of fat, of hardstock fats.
 3. Product according toclaim 1 which comprises a hardstock consisting of over 80 % by weight ofhardstock indigestible polyol fatty acid polyesters.
 4. Productaccording to claim 1 wherein said hardstock indigestible polyol fattyacid polyesters have a slip melting point of from 37° to 55° C. 5.Product according to claim 1 wherein at least 50 % by weight of thetotal amount of digestible fatty acid residues consists ofpolyunsaturated fatty acid residues.
 6. Product according to claim 1which is a water-in-oil emulsion or oil-in-water-in-oil emulsioncontaining 65 to 90 % by weight of fat.
 7. Product according to claim 1which is a water-in-oil emulsion or oil-in-water-in-oil emulsioncontaining 35 to 65 % by weight of fat.
 8. A process for the preparationof edible fat-containing products comprising at least 5%, calculated byweight of the total amount of fat, of hardstock indigestible polyolfatty acid polyesters, the process comprising the step of initiallyprocessing said fat-containing product in two or more separatefat-containing fractions under such conditions that the fat in at leastone of said fractions has partly or fully crystallized before said twoor more fractions have been fully mixed, at least one of said fractionsincluding an indigestible polyol fatty acid polyester.
 9. Processaccording to claim 8 wherein the fat phase of a first separatelyprocessed fat-containing fraction has a slip melting point of below 35°C.
 10. Process according to claim 8 wherein a first fat-containingfraction is separately processed such that it comprises 2 to 20 % byweight of crystallized fat before said full mixing.
 11. Processaccording to claim 8 wherein the fat phase of a second separatelyprocessed fat-containing fraction has a slip melting point of between40° and 50° C.
 12. Process according to claim 8 wherein a secondseparately processed fat-containing fraction comprises at least 60 % byweight of the hardstock fats of the product.
 13. Process according toclaim 8 wherein a second fat-containing fraction is separately processedsuch that it comprises 2 to 30 % by weight of crystallized fat beforesaid full mixing.
 14. Process according to claim 8 wherein a first fator fat blend is emulsified with an aqueous phase, the temperature of theresulting emulsion is adjusted to a value below 15° C., and subsequentlysaid emulsion is mixed with a second fraction essentially consisting ofa second fat or fat blend having a slip melting point above that of thefirst fat or fat blend.
 15. Process according to claim 8 whereinfat-soluble vitamins are incorporated into a first separately processedfraction substantially free from any indigestible polyol fatty acidpolyesters.